Statistics
| Branch: | Revision:

ffmpeg / libavformat / segafilm.c @ 916bf03a

History | View | Annotate | Download (9.33 KB)

1
/*
2
 * Sega FILM Format (CPK) Demuxer
3
 * Copyright (c) 2003 The ffmpeg Project
4
 *
5
 * This file is part of FFmpeg.
6
 *
7
 * FFmpeg is free software; you can redistribute it and/or
8
 * modify it under the terms of the GNU Lesser General Public
9
 * License as published by the Free Software Foundation; either
10
 * version 2.1 of the License, or (at your option) any later version.
11
 *
12
 * FFmpeg is distributed in the hope that it will be useful,
13
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15
 * Lesser General Public License for more details.
16
 *
17
 * You should have received a copy of the GNU Lesser General Public
18
 * License along with FFmpeg; if not, write to the Free Software
19
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20
 */
21

    
22
/**
23
 * @file segafilm.c
24
 * Sega FILM (.cpk) file demuxer
25
 * by Mike Melanson (melanson@pcisys.net)
26
 * For more information regarding the Sega FILM file format, visit:
27
 *   http://www.pcisys.net/~melanson/codecs/
28
 */
29

    
30
#include "avformat.h"
31

    
32
#define FILM_TAG MKBETAG('F', 'I', 'L', 'M')
33
#define FDSC_TAG MKBETAG('F', 'D', 'S', 'C')
34
#define STAB_TAG MKBETAG('S', 'T', 'A', 'B')
35
#define CVID_TAG MKBETAG('c', 'v', 'i', 'd')
36

    
37
typedef struct {
38
  int stream;
39
  offset_t sample_offset;
40
  unsigned int sample_size;
41
  int64_t pts;
42
  int keyframe;
43
} film_sample_t;
44

    
45
typedef struct FilmDemuxContext {
46
    int video_stream_index;
47
    int audio_stream_index;
48

    
49
    unsigned int audio_type;
50
    unsigned int audio_samplerate;
51
    unsigned int audio_bits;
52
    unsigned int audio_channels;
53

    
54
    unsigned int video_type;
55
    unsigned int sample_count;
56
    film_sample_t *sample_table;
57
    unsigned int current_sample;
58

    
59
    unsigned int base_clock;
60
    unsigned int version;
61

    
62
    /* buffer used for interleaving stereo PCM data */
63
    unsigned char *stereo_buffer;
64
    int stereo_buffer_size;
65
} FilmDemuxContext;
66

    
67
static int film_probe(AVProbeData *p)
68
{
69
    if (p->buf_size < 4)
70
        return 0;
71

    
72
    if (AV_RB32(&p->buf[0]) != FILM_TAG)
73
        return 0;
74

    
75
    return AVPROBE_SCORE_MAX;
76
}
77

    
78
static int film_read_header(AVFormatContext *s,
79
                            AVFormatParameters *ap)
80
{
81
    FilmDemuxContext *film = (FilmDemuxContext *)s->priv_data;
82
    ByteIOContext *pb = &s->pb;
83
    AVStream *st;
84
    unsigned char scratch[256];
85
    int i;
86
    unsigned int data_offset;
87
    unsigned int audio_frame_counter;
88

    
89
    film->sample_table = NULL;
90
    film->stereo_buffer = NULL;
91
    film->stereo_buffer_size = 0;
92

    
93
    /* load the main FILM header */
94
    if (get_buffer(pb, scratch, 16) != 16)
95
        return AVERROR_IO;
96
    data_offset = AV_RB32(&scratch[4]);
97
    film->version = AV_RB32(&scratch[8]);
98

    
99
    /* load the FDSC chunk */
100
    if (film->version == 0) {
101
        /* special case for Lemmings .film files; 20-byte header */
102
        if (get_buffer(pb, scratch, 20) != 20)
103
            return AVERROR_IO;
104
        /* make some assumptions about the audio parameters */
105
        film->audio_type = CODEC_ID_PCM_S8;
106
        film->audio_samplerate = 22050;
107
        film->audio_channels = 1;
108
        film->audio_bits = 8;
109
    } else {
110
        /* normal Saturn .cpk files; 32-byte header */
111
        if (get_buffer(pb, scratch, 32) != 32)
112
            return AVERROR_IO;
113
        film->audio_samplerate = AV_RB16(&scratch[24]);;
114
        film->audio_channels = scratch[21];
115
        film->audio_bits = scratch[22];
116
        if (film->audio_bits == 8)
117
            film->audio_type = CODEC_ID_PCM_S8;
118
        else if (film->audio_bits == 16)
119
            film->audio_type = CODEC_ID_PCM_S16BE;
120
        else
121
            film->audio_type = 0;
122
    }
123

    
124
    if (AV_RB32(&scratch[0]) != FDSC_TAG)
125
        return AVERROR_INVALIDDATA;
126

    
127
    if (AV_RB32(&scratch[8]) == CVID_TAG) {
128
        film->video_type = CODEC_ID_CINEPAK;
129
    } else
130
        film->video_type = 0;
131

    
132
    /* initialize the decoder streams */
133
    if (film->video_type) {
134
        st = av_new_stream(s, 0);
135
        if (!st)
136
            return AVERROR_NOMEM;
137
        film->video_stream_index = st->index;
138
        st->codec->codec_type = CODEC_TYPE_VIDEO;
139
        st->codec->codec_id = film->video_type;
140
        st->codec->codec_tag = 0;  /* no fourcc */
141
        st->codec->width = AV_RB32(&scratch[16]);
142
        st->codec->height = AV_RB32(&scratch[12]);
143
    }
144

    
145
    if (film->audio_type) {
146
        st = av_new_stream(s, 0);
147
        if (!st)
148
            return AVERROR_NOMEM;
149
        film->audio_stream_index = st->index;
150
        st->codec->codec_type = CODEC_TYPE_AUDIO;
151
        st->codec->codec_id = film->audio_type;
152
        st->codec->codec_tag = 1;
153
        st->codec->channels = film->audio_channels;
154
        st->codec->bits_per_sample = film->audio_bits;
155
        st->codec->sample_rate = film->audio_samplerate;
156
        st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
157
            st->codec->bits_per_sample;
158
        st->codec->block_align = st->codec->channels *
159
            st->codec->bits_per_sample / 8;
160
    }
161

    
162
    /* load the sample table */
163
    if (get_buffer(pb, scratch, 16) != 16)
164
        return AVERROR_IO;
165
    if (AV_RB32(&scratch[0]) != STAB_TAG)
166
        return AVERROR_INVALIDDATA;
167
    film->base_clock = AV_RB32(&scratch[8]);
168
    film->sample_count = AV_RB32(&scratch[12]);
169
    if(film->sample_count >= UINT_MAX / sizeof(film_sample_t))
170
        return -1;
171
    film->sample_table = av_malloc(film->sample_count * sizeof(film_sample_t));
172

    
173
    for(i=0; i<s->nb_streams; i++)
174
        av_set_pts_info(s->streams[i], 33, 1, film->base_clock);
175

    
176
    audio_frame_counter = 0;
177
    for (i = 0; i < film->sample_count; i++) {
178
        /* load the next sample record and transfer it to an internal struct */
179
        if (get_buffer(pb, scratch, 16) != 16) {
180
            av_free(film->sample_table);
181
            return AVERROR_IO;
182
        }
183
        film->sample_table[i].sample_offset =
184
            data_offset + AV_RB32(&scratch[0]);
185
        film->sample_table[i].sample_size = AV_RB32(&scratch[4]);
186
        if (AV_RB32(&scratch[8]) == 0xFFFFFFFF) {
187
            film->sample_table[i].stream = film->audio_stream_index;
188
            film->sample_table[i].pts = audio_frame_counter;
189
            film->sample_table[i].pts *= film->base_clock;
190
            film->sample_table[i].pts /= film->audio_samplerate;
191

    
192
            audio_frame_counter += (film->sample_table[i].sample_size /
193
                (film->audio_channels * film->audio_bits / 8));
194
        } else {
195
            film->sample_table[i].stream = film->video_stream_index;
196
            film->sample_table[i].pts = AV_RB32(&scratch[8]) & 0x7FFFFFFF;
197
            film->sample_table[i].keyframe = (scratch[8] & 0x80) ? 0 : 1;
198
        }
199
    }
200

    
201
    film->current_sample = 0;
202

    
203
    return 0;
204
}
205

    
206
static int film_read_packet(AVFormatContext *s,
207
                            AVPacket *pkt)
208
{
209
    FilmDemuxContext *film = (FilmDemuxContext *)s->priv_data;
210
    ByteIOContext *pb = &s->pb;
211
    film_sample_t *sample;
212
    int ret = 0;
213
    int i;
214
    int left, right;
215

    
216
    if (film->current_sample >= film->sample_count)
217
        return AVERROR_IO;
218

    
219
    sample = &film->sample_table[film->current_sample];
220

    
221
    /* position the stream (will probably be there anyway) */
222
    url_fseek(pb, sample->sample_offset, SEEK_SET);
223

    
224
    /* do a special song and dance when loading FILM Cinepak chunks */
225
    if ((sample->stream == film->video_stream_index) &&
226
        (film->video_type == CODEC_ID_CINEPAK)) {
227
        pkt->pos= url_ftell(pb);
228
        if (av_new_packet(pkt, sample->sample_size))
229
            return AVERROR_NOMEM;
230
        get_buffer(pb, pkt->data, sample->sample_size);
231
    } else if ((sample->stream == film->audio_stream_index) &&
232
        (film->audio_channels == 2)) {
233
        /* stereo PCM needs to be interleaved */
234

    
235
        if (av_new_packet(pkt, sample->sample_size))
236
            return AVERROR_NOMEM;
237

    
238
        /* make sure the interleave buffer is large enough */
239
        if (sample->sample_size > film->stereo_buffer_size) {
240
            av_free(film->stereo_buffer);
241
            film->stereo_buffer_size = sample->sample_size;
242
            film->stereo_buffer = av_malloc(film->stereo_buffer_size);
243
        }
244

    
245
        pkt->pos= url_ftell(pb);
246
        ret = get_buffer(pb, film->stereo_buffer, sample->sample_size);
247
        if (ret != sample->sample_size)
248
            ret = AVERROR_IO;
249

    
250
        left = 0;
251
        right = sample->sample_size / 2;
252
        for (i = 0; i < sample->sample_size; ) {
253
            if (film->audio_bits == 8) {
254
                pkt->data[i++] = film->stereo_buffer[left++];
255
                pkt->data[i++] = film->stereo_buffer[right++];
256
            } else {
257
                pkt->data[i++] = film->stereo_buffer[left++];
258
                pkt->data[i++] = film->stereo_buffer[left++];
259
                pkt->data[i++] = film->stereo_buffer[right++];
260
                pkt->data[i++] = film->stereo_buffer[right++];
261
            }
262
        }
263
    } else {
264
        ret= av_get_packet(pb, pkt, sample->sample_size);
265
        if (ret != sample->sample_size)
266
            ret = AVERROR_IO;
267
    }
268

    
269
    pkt->stream_index = sample->stream;
270
    pkt->pts = sample->pts;
271

    
272
    film->current_sample++;
273

    
274
    return ret;
275
}
276

    
277
static int film_read_close(AVFormatContext *s)
278
{
279
    FilmDemuxContext *film = (FilmDemuxContext *)s->priv_data;
280

    
281
    av_free(film->sample_table);
282
    av_free(film->stereo_buffer);
283

    
284
    return 0;
285
}
286

    
287
AVInputFormat segafilm_demuxer = {
288
    "film_cpk",
289
    "Sega FILM/CPK format",
290
    sizeof(FilmDemuxContext),
291
    film_probe,
292
    film_read_header,
293
    film_read_packet,
294
    film_read_close,
295
};